Process

Quality DLC Deposition

DLC coatings can be deposited using a variety of deposition methods such as sputtering, ion beam, cathodic arc, electron beam, lasers and PACVD. NCT deposits our diamond like carbon coatings using our partner The HEF Group’s patented technology combining PVD and PACVD which deposits some of the highest quality, most consistent DLC coatings available to industry today.

This technology allows the DLC coatings to be deposited in large scale production machines without sacrificing film quality. With HEF’s patented technology, we have the ability to deposit PVD layers as well as dense, uniform PACVD layers in the same system. Our process will transition from PVD layers to DLC layers seamlessly producing films that exhibit excellent interlayer adhesion as well as excellent adhesion to the substrate. The PACVD process NCT utilizes will deposit a DLC coating that will have no noticeable effect on your product’s surface finish.

Coating Process

The product is placed into the stainless steel vacuum chamber on a fixturing carousel and the chamber is evacuated. The product is preheated to a low processing temperature that will not exceed (150 c) 300 F. The preheating phase of the process conditions the substrate for the coating and will ensure that all of the moisture absorbed by the material has been outgassed before the deposition process begins.

After the preheat cycle is complete, the process transitions into the ion etching phase where product is bombarded with ions from argon gas to scrub or sputter clean the surface and remove micro oxides. This scrubbing of the surface with ions cleans the surface and improves the adhesion of the coating to the substrate.

After the substrate has been sputter cleaned, the process transitions into the coating phase. If an initial layer (underlayer) is needed to improve the performance of the product in the final use, the high energy sputtering process developed by The HEF Group is used to deposit a dense well adhered smooth underlayer. As the underlayer coating reaches the proper thickness, the process transitions into the DLC coating step which deposits a dense, smooth amorphous carbon hydrogenated(a-C:H) layer onto the product’s surface.

Underlayers

Underlayers can be deposited to improve the coating’s performance in certain applications.

If no underlayer is required, a dense uniform coating of DLC can be deposited directly to the substrate as well.

Dense smooth a-C:H DLC Diamond like Carbon Coating

Coating Phase

During the DLC coating phase of the process, a carbon carrying gas is introduced into the chamber. This gas is the source for the amorphous carbon DLC coating. Using HEF’s patented CAM technology, the carbon carrying gas introduced into the chamber is ionized by auxiliary anodes and undergoes what is referred to as “cracking” or separating of the hydrogen and carbon in the gas. The ionized hydrogen and carbon atoms in the gas are drawn to the surface of the product with an electrical charge that is applied to the carousel.

Final Steps

The carousel that has the electrical charge applied and is carrying the product to be coated is also rotating in the chamber and draws the ionized carbon/hydrogen ions to the surface of the product forming the amorphous carbon or diamond like carbon film.

The rotation of the carousel carrying the product in the chamber can be a single, double or triple axis rotation depending on the complexity of the product geometry and the coating uniformity required. This allows a uniform film to be deposited on the surface of the product unlike conventional plating processes.

Film properties, structure, hardness and underlayers can all be tuned to produce a coating optimized for a customer’s requirements.